The fingernail is composed primarily of hard keratin, which is a mixture of proteins hardened by its calcium content and disulfide bonding. An excellent review of the fingernail chemistry appears in the Archives of Dermatology--Vol. 94,November 1966. This article confirms the effect of calcium on nail hardness.
Fluorides have been used extensively to increase the hardness of nails. Teeth have long benefited from the topical application of fluoride typically applied directly from toothpaste. It is generally believed that the effectiveness of fluoride in strengthening teeth, bone or nails results from the formation of insoluble calcium fluoride compounds where the source of the calcium exist naturally in the structure being treated. Nails contain calcium naturally. Busch (the current inventor) discloses in U.S. Pat. No. 5,478,551 that the physical strength of nails can be increased by applying fluoride solutions thereto.
It is believed that fluoride treatment of teeth, bone and fingernails is effective because these materials naturally contain the necessary calcium available for combination with fluoride.
The fingernail contains the least amount of natural calcium of the group consisting of bone, teeth and fingernails. While the calcium content of teeth and bone exceed 20% in various forms; the calcium content of fingernails is about 0.1%.
Various calcium treatment products for increasing the calcium content of fingernails in order to strengthen them exist in the current marketplace. Typical products of this type contain calcium compounds dispersed in a nitro cellulose lacquer. No specific claims are made for the calcium compounds and it is generally understood that the strengthening benefit is derived primarily from the lacquer coating.
The cells that make up the nail structure are dead, and it is unlikely that calcium in this form provides a significant benefit to the nail.
None of the calcium products in the current art are known to permanently strengthen the nail. There are no prior art references for increasing the calcium content of the fingernail known to the present inventor.
The present invention is directed toward increasing the amount of calcium in the nail thereby increasing the effectiveness of fluoride as a strengthening agent thereby increasing the strength of the nail.